The present invention generally relates to monitoring of broadcast signals, and more particularly to detection of time-compressed broadcast content.
Accurate information about broadcast of television content such as programs, commercials, infomercials, etc., by television stations is obtained for a variety of reasons, including, creating a record by which content owners may bill television stations for use of their content, for purposes of generating ratings data and for purposes of verifying that local stations broadcast content provided by their national affiliates. Syndication houses, for example, create television programs for distribution to television stations for broadcast in exchange for a usage fee.
To track broadcast television content, content owners often use commercially available encoders to insert a unique source identifier (SID) and a date and time stamp into the content before providing the content to television stations. When broadcasted, the encoded content is received by a monitoring station that monitors broadcast signals in the broadcast areas of interest. The monitoring station detects and decodes the SID and date/time stamp inserted in the content, and uses this information to uniquely identify the content and determine the number of times that the content has been broadcasted in the broadcast area where the monitoring station is situated. This information is reported to the content owners, to be used in reconciling payments owed by the television stations to the content owners. This information is also reported to the national networks to verify that local stations broadcast national content supplied by the national networks, and may additionally be used to identify programs for purposes of generating television ratings.
Recently, some television broadcasters have been “time compressing” television content to reduce the length of the content time. Time compression is not discernable to the television audience, can be easily performed using commercially available lime compression devices, and generally involves periodically removing video frames from the recorded content and adjusting the audio, thereby reducing the time required to broadcast it. For example, a thirty minute program might be reduced, i.e., time compressed, by thirty seconds to enable the broadcaster to add an additional commercial in that thirty second period, thereby generating additional revenue from the commercial time. Unfortunately, time compression is not detectable by existing broadcast signal monitoring systems such that content owners have no way of knowing whether their content has been broadcast in a compressed or uncompressed format.